<template>
  <div class="login">
    <!--  顶部  -->
    <div class="el-login-header">
      <logo style="width: 40px;height: 40px;"></logo>
      <span>铁路牵引供电智能运维系统</span>
    </div>
    <el-form ref="loginForm" :model="loginForm" :rules="loginRules" class="login-form">
      <h3 class="title">
        <logo style="width: 24px;height: 24px;"></logo>
        <span style="margin-left: 12px;">铁路牵引供电智能运维系统</span>
      </h3>
      <el-form-item prop="username">
        <el-input
            v-model="loginForm.username"
            type="text"
            auto-complete="off"
            placeholder="账号"
        >
          <svg-icon slot="prefix" icon-class="user" class="el-input__icon input-icon"/>
        </el-input>
      </el-form-item>
      <el-form-item prop="password">
        <el-input
            v-model="loginForm.password"
            type="password"
            auto-complete="off"
            placeholder="密码"
            @keyup.enter.native="handleLogin"
        >
          <svg-icon slot="prefix" icon-class="password" class="el-input__icon input-icon"/>
        </el-input>
      </el-form-item>
      <el-form-item prop="code" v-if="captchaEnabled">
        <el-input
            v-model="loginForm.code"
            auto-complete="off"
            placeholder="验证码"
            style="width: 63%"
            @keyup.enter.native="handleLogin"
        >
          <svg-icon slot="prefix" icon-class="validCode" class="el-input__icon input-icon"/>
        </el-input>
        <div class="login-code">
          <!--          <img :src="codeUrl" @click="getCode" class="login-code-img"/>-->
          <canvas id="canvas" width="100" height="40" @click="initCanvas"></canvas>
        </div>
      </el-form-item>
      <el-checkbox v-model="loginForm.rememberMe" style="margin:0px 0px 25px 0px;">记住密码</el-checkbox>
      <el-form-item style="width:100%;">
        <el-button
            :loading="loading"
            size="medium"
            type="primary"
            style="width:100%;"
            @click.native.prevent="handleLogin"
        >
          <span v-if="!loading">登 录</span>
          <span v-else>登 录 中...</span>
        </el-button>
        <div style="float: right;" v-if="register">
          <router-link class="link-type" :to="'/register'">立即注册</router-link>
        </div>
      </el-form-item>
    </el-form>
    <!--  底部  -->
    <div class="el-login-footer">

    </div>
  </div>
</template>

<script>
import Cookies from 'js-cookie'
import { decrypt, encrypt } from '@/utils/jsencrypt'
import Logo from '@/views/logo.vue'

export default {
  name: 'Login',
  components: { Logo },
  data() {
    return {
      codeUrl: '',
      loginForm: {
        username: '',
        password: '',
        rememberMe: false,
        code: '',
        uuid: ''
      },
      loginRules: {
        username: [
          { required: true, trigger: 'blur', message: '请输入您的账号' }
        ],
        password: [
          { required: true, trigger: 'blur', message: '请输入您的密码' }
        ],
        code: [{ required: true, trigger: 'change', message: '请输入验证码' }, {
          validator: this.checkCode,
          trigger: 'blur'
        }]
      },
      loading: false,
      // 验证码开关
      captchaEnabled: true,
      // 注册开关
      register: false,
      redirect: undefined,
      captchaCode: ''
    }
  },
  watch: {
    $route: {
      handler: function(route) {
        this.redirect = route.query && route.query.redirect
      },
      immediate: true
    }
  },
  created() {
    // this.getCode()
    this.getCookie()
  },
  mounted() {
    this.initCanvas()
  },
  methods: {
    checkCode(rule, value, callback) {
      if (value === '' || !value) {
        callback(new Error('请输入验证码'))
      } else if (this.captchaCode && value.toLocaleUpperCase() !== this.captchaCode.toLocaleUpperCase()) {
        callback(new Error('验证码错误'))
      } else {
        callback()
      }
    },
    /* getCode() {
      getCodeImg().then(res => {
        this.captchaEnabled = res.captchaEnabled === undefined ? true : res.captchaEnabled
        if (this.captchaEnabled) {
          this.codeUrl = 'data:image/gif;base64,' + res.img
          this.loginForm.uuid = res.uuid
        }
      })
    }, */
    //初始化验证码
    initCanvas() {
      let show_num = []
      let canvas_width = document.getElementById('canvas').offsetWidth
      let canvas_height = document.getElementById('canvas').offsetHeight
      let canvas = document.getElementById('canvas')//获取到canvas的对象，演员
      let context = canvas.getContext('2d')//获取到canvas画图的环境，演员表演的舞台
      canvas.width = canvas_width
      canvas.height = canvas_height
      let sCode = 'a,b,c,d,e,f,g,h,i,j,k,m,n,p,q,r,s,t,u,v,w,x,y,z,A,B,C,E,F,G,H,J,K,L,M,N,P,Q,R,S,T,W,X,Y,Z,1,2,3,4,5,6,7,8,9,0'
      let aCode = sCode.split(',')
      let aLength = aCode.length//获取到数组的长度
      for (let i = 0; i < 4; i++) { //这里的for循环可以控制验证码位数（如果想显示6位数，4改成6即可）
        let j = Math.floor(Math.random() * aLength)//获取到随机的索引值
        // let deg = Math.random() * 30 * Math.PI / 180;//产生0~30之间的随机弧度
        let deg = Math.random() - 0.5 //产生一个随机弧度
        let txt = aCode[j]//得到随机的一个内容
        show_num[i] = txt.toLowerCase()

        let x = 10 + i * 20//文字在canvas上的x坐标
        let y = 20 + Math.random() * 8//文字在canvas上的y坐标
        context.font = 'bold 23px 微软雅黑'
        context.translate(x, y)
        context.rotate(deg)
        context.fillStyle = this.randomColor()
        context.fillText(txt, 0, 0)
        context.rotate(-deg)
        context.translate(-x, -y)
      }
      this.captchaCode = show_num.join('')
      for (let i = 0; i <= 5; i++) { //验证码上显示线条
        context.strokeStyle = this.randomColor()
        context.beginPath()
        context.moveTo(Math.random() * canvas_width, Math.random() * canvas_height)
        context.lineTo(Math.random() * canvas_width, Math.random() * canvas_height)
        context.stroke()
      }
      for (let i = 0; i <= 30; i++) { //验证码上显示小点
        context.strokeStyle = this.randomColor()
        context.beginPath()
        let x = Math.random() * canvas_width
        let y = Math.random() * canvas_height
        context.moveTo(x, y)
        context.lineTo(x + 1, y + 1)
        context.stroke()
      }
    },
    //验证码随机颜色
    randomColor() {
      let r = Math.floor(Math.random() * 256)
      let g = Math.floor(Math.random() * 256)
      let b = Math.floor(Math.random() * 256)
      // console.log("rgb(" + r + "," + g + "," + b + ")")
      // return "rgb(" + r + "," + g + "," + b + ")";
      // return 'rgb(130,41,157)'
      return "#257FDD"
    },
    getCookie() {
      const username = Cookies.get('username')
      const password = Cookies.get('password')
      const rememberMe = Cookies.get('rememberMe')
      this.loginForm = {
        username: username === undefined ? this.loginForm.username : username,
        password: password === undefined ? this.loginForm.password : decrypt(password),
        rememberMe: rememberMe === undefined ? false : Boolean(rememberMe)
      }
    },
    handleLogin() {
      this.$refs.loginForm.validate(valid => {
        if (valid) {
          this.loading = true
          if (this.loginForm.rememberMe) {
            Cookies.set('username', this.loginForm.username, { expires: 30 })
            Cookies.set('password', encrypt(this.loginForm.password), { expires: 30 })
            Cookies.set('rememberMe', this.loginForm.rememberMe, { expires: 30 })
          } else {
            Cookies.remove('username')
            Cookies.remove('password')
            Cookies.remove('rememberMe')
          }
          this.$store.dispatch('Login', this.loginForm).then(() => {
            this.$router.push({ path: this.redirect || '/' }).catch(() => {
            })
          }).catch(() => {
            this.loading = false
            if (this.captchaEnabled) {
              this.initCanvas()
            }
          })
        }
      })
    }
  }
}
</script>

<style rel="stylesheet/scss" lang="scss">
.login {
  display: flex;
  justify-content: flex-end;
  align-items: center;
  height: 100%;
  background: url("../assets/customImg/logo-bg.png") no-repeat;
  background-size: 100% 100%;
  padding-right: 10%;
}

.title {
  margin: 0px auto 30px auto;
  text-align: center;
  color: #494949;
  display: flex;
  justify-content: center;
  align-items: center;
}

.login-form {
  border-radius: 6px;
  background: #ffffff;
  width: 400px;
  padding: 25px 25px 5px 25px;

  .el-input {
    height: 38px;

    input {
      height: 38px;
    }
  }

  .input-icon {
    height: 39px;
    width: 14px;
    margin-left: 2px;
  }
}

.login-tip {
  font-size: 13px;
  text-align: center;
  color: #bfbfbf;
}

.login-code {
  width: 33%;
  height: 38px;
  float: right;

  img {
    cursor: pointer;
    vertical-align: middle;
  }
}

.el-login-footer {
  height: 40px;
  line-height: 40px;
  position: fixed;
  bottom: 0;
  width: 100%;
  text-align: center;
  color: #fff;
  font-family: Arial;
  font-size: 12px;
  letter-spacing: 1px;
}

.el-login-header {
  position: fixed;
  top: 5%;
  left: 0;
  padding-left: 3%;
  width: 100%;
  color: #fff;
  font-size: 34px;
  letter-spacing: 1px;
  display: flex;
  justify-content: flex-start;
  align-items: center;

  span {
    margin-left: 20px;
  }
}

.login-code-img {
  height: 38px;
}


</style>
<style lang="scss" scoped>
::v-deep .el-button--primary {
  background-color: #3196FA;
  border-color: #3196FA;
}

::v-deep .el-button--primary:hover {
  background-color: #2680DE !important;
}

.ground-glass {
  background-color: rgb(255 255 255 / 20%);
  backdrop-filter: blur(5px);
}
</style>
